Finnish President Sauli Niinisto and Prime Minister Sanna Marin have announced that Finland must apply to join the NATO military alliance “without delay”.
Finland, which shares a 1,300km (810 mile) border and a difficult past with Russia, has gradually stepped up its cooperation with NATO as a partner since Russia annexed Ukraine’s Crimean peninsula in 2014.
But until Russia’s full-scale invasion of Ukraine in February, the Nordic country had refrained from joining in order to maintain friendly relations with its eastern neighbour.
“Finland must apply for NATO membership without delay,” Niinisto and Marin said in a joint statement.
“We hope that the national steps still needed to make this decision will be taken rapidly within the next few days.”
NATO Secretary General Jens Stoltenberg said any accession process would be “smooth and swift” and that Finland “would be warmly welcomed”.
Russia warned on Thursday it would have to take “military-technical” steps in response to Finland joining NATO.
“The expansion of NATO and the approach of the alliance to our borders does not make the world and our continent more stable and secure,” Kremlin spokesman Dmitry Peskov told reporters.
When asked whether Finland’s membership would be a threat, Peskov answered: “definitely”.
“Everything will depend on how this process takes place, how far the military infrastructure will move towards our borders,” he said.
Russia’s foreign ministry said Moscow would be “forced to take reciprocal steps, military-technical and other, to address the resulting threats to its national security”.
It accused NATO of seeking to create “another flank for the military threat to our country”.
“Helsinki should be aware of its responsibility and the consequences of such a move,” the foreign ministry said.
The view among Finns on NATO has changed rapidly after Russia initiated what it calls a “special operation” in Ukraine.
Finnish public support for joining NATO has risen to record numbers over recent months.
The latest poll by public broadcaster YLE showed 76 percent of Finns in favour and just 12 percent against it, while support for membership used to linger at only about 25 percent for years prior to the all-out war in Ukraine.
While military non-alignment has long satisfied many Finns as a way of staying out of conflicts, Russia’s invasion of sovereign Ukraine has led an increasing number of Finns to view friendly relations with Russia as an empty phrase.
Ukraine’s fate has been particularly disturbing for Finland to watch as it fought two wars with Russia between 1939 and 1944, repelling an attempted invasion but losing approximately 10 percent of its territory in the subsequent peace agreement.
Finland’s rapid shift towards NATO is likely to pull along neighbouring Sweden, which is due to announce its decision on the membership application on May 15.